1 /*
   2  * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 #ifndef SHARE_GC_Z_ZBARRIER_HPP
  25 #define SHARE_GC_Z_ZBARRIER_HPP
  26 
  27 #include "memory/allocation.hpp"
  28 #include "oops/oop.hpp"
  29 #include "oops/valueKlass.hpp"
  30 
  31 typedef bool (*ZBarrierFastPath)(uintptr_t);
  32 typedef uintptr_t (*ZBarrierSlowPath)(uintptr_t);
  33 
  34 class ZBarrier : public AllStatic {
  35 private:
  36   static const bool Follow      = true;
  37   static const bool DontFollow  = false;
  38 
  39   static const bool Strong      = false;
  40   static const bool Finalizable = true;
  41 
  42   static const bool Publish     = true;
  43   static const bool Overflow    = false;
  44 
  45   template <ZBarrierFastPath fast_path, ZBarrierSlowPath slow_path> static oop barrier(volatile oop* p, oop o);
  46   template <ZBarrierFastPath fast_path, ZBarrierSlowPath slow_path> static oop weak_barrier(volatile oop* p, oop o);
  47   template <ZBarrierFastPath fast_path, ZBarrierSlowPath slow_path> static void root_barrier(oop* p, oop o);
  48 
  49   static bool is_null_fast_path(uintptr_t addr);
  50   static bool is_good_or_null_fast_path(uintptr_t addr);
  51   static bool is_weak_good_or_null_fast_path(uintptr_t addr);
  52 
  53   static bool is_resurrection_blocked(volatile oop* p, oop* o);
  54 
  55   static bool during_mark();
  56   static bool during_relocate();
  57   template <bool finalizable> static bool should_mark_through(uintptr_t addr);
  58   template <bool follow, bool finalizable, bool publish> static uintptr_t mark(uintptr_t addr);
  59   static uintptr_t remap(uintptr_t addr);
  60   static uintptr_t relocate(uintptr_t addr);
  61   static uintptr_t relocate_or_mark(uintptr_t addr);
  62   static uintptr_t relocate_or_remap(uintptr_t addr);
  63 
  64   static uintptr_t load_barrier_on_oop_slow_path(uintptr_t addr);
  65 
  66   static uintptr_t weak_load_barrier_on_oop_slow_path(uintptr_t addr);
  67   static uintptr_t weak_load_barrier_on_weak_oop_slow_path(uintptr_t addr);
  68   static uintptr_t weak_load_barrier_on_phantom_oop_slow_path(uintptr_t addr);
  69 
  70   static uintptr_t keep_alive_barrier_on_weak_oop_slow_path(uintptr_t addr);
  71   static uintptr_t keep_alive_barrier_on_phantom_oop_slow_path(uintptr_t addr);
  72 
  73   static uintptr_t mark_barrier_on_oop_slow_path(uintptr_t addr);
  74   static uintptr_t mark_barrier_on_finalizable_oop_slow_path(uintptr_t addr);
  75   static uintptr_t mark_barrier_on_root_oop_slow_path(uintptr_t addr);
  76   static uintptr_t mark_barrier_on_invisible_root_oop_slow_path(uintptr_t addr);
  77 
  78   static uintptr_t relocate_barrier_on_root_oop_slow_path(uintptr_t addr);
  79 
  80 public:
  81   // Load barrier
  82   static  oop load_barrier_on_oop(oop o);
  83   static  oop load_barrier_on_oop_field(volatile oop* p);
  84   static  oop load_barrier_on_oop_field_preloaded(volatile oop* p, oop o);
  85   static void load_barrier_on_oop_array(volatile oop* p, size_t length);
  86   static void load_barrier_on_oop_fields(oop o);
  87   static  oop load_barrier_on_weak_oop_field_preloaded(volatile oop* p, oop o);
  88   static  oop load_barrier_on_phantom_oop_field_preloaded(volatile oop* p, oop o);
  89   static void load_barrier_on_root_oop_field(oop* p);
  90 
  91   // Weak load barrier
  92   static oop weak_load_barrier_on_oop_field(volatile oop* p);
  93   static oop weak_load_barrier_on_oop_field_preloaded(volatile oop* p, oop o);
  94   static oop weak_load_barrier_on_weak_oop(oop o);
  95   static oop weak_load_barrier_on_weak_oop_field(volatile oop* p);
  96   static oop weak_load_barrier_on_weak_oop_field_preloaded(volatile oop* p, oop o);
  97   static oop weak_load_barrier_on_phantom_oop(oop o);
  98   static oop weak_load_barrier_on_phantom_oop_field(volatile oop* p);
  99   static oop weak_load_barrier_on_phantom_oop_field_preloaded(volatile oop* p, oop o);
 100 
 101   // Is alive barrier
 102   static bool is_alive_barrier_on_weak_oop(oop o);
 103   static bool is_alive_barrier_on_phantom_oop(oop o);
 104 
 105   // Keep alive barrier
 106   static void keep_alive_barrier_on_weak_oop_field(volatile oop* p);
 107   static void keep_alive_barrier_on_phantom_oop_field(volatile oop* p);
 108   static void keep_alive_barrier_on_phantom_root_oop_field(oop* p);
 109 
 110   // Mark barrier
 111   static void mark_barrier_on_oop_field(volatile oop* p, bool finalizable);
 112   static void mark_barrier_on_oop_array(volatile oop* p, size_t length, bool finalizable);
 113   static void mark_barrier_on_root_oop_field(oop* p);
 114   static void mark_barrier_on_invisible_root_oop_field(oop* p);
 115 
 116   // Relocate barrier
 117   static void relocate_barrier_on_root_oop_field(oop* p);
 118 
 119   // Narrow oop variants, never used.
 120   static oop  load_barrier_on_oop_field(volatile narrowOop* p);
 121   static oop  load_barrier_on_oop_field_preloaded(volatile narrowOop* p, oop o);
 122   static void load_barrier_on_oop_array(volatile narrowOop* p, size_t length);
 123   static oop  load_barrier_on_weak_oop_field_preloaded(volatile narrowOop* p, oop o);
 124   static oop  load_barrier_on_phantom_oop_field_preloaded(volatile narrowOop* p, oop o);
 125   static oop  weak_load_barrier_on_oop_field_preloaded(volatile narrowOop* p, oop o);
 126   static oop  weak_load_barrier_on_weak_oop_field_preloaded(volatile narrowOop* p, oop o);
 127   static oop  weak_load_barrier_on_phantom_oop_field_preloaded(volatile narrowOop* p, oop o);
 128 };
 129 
 130 #endif // SHARE_GC_Z_ZBARRIER_HPP